Scientists find link between photosynthesis and 'fifth state of matter'

Inside a lab, scientists marvel at a strange state that forms when they cool down atoms to nearly absolute zero. Outside their window, trees gather sunlight and turn them into new leaves. The two seem unrelated—but a new study suggests that these processes aren't so different as they might appear on the surface.

The study, published in PRX Energy on April 28, found links at the atomic level between photosynthesis and exciton condensates—a strange state of physics that allows energy to flow frictionlessly through a material. The finding is scientifically intriguing and may suggest new ways to think about designing electronics, the researchers say.

Modeling the complicated interactions of atoms and molecules as they display interesting properties is not possible to see  with the naked eye, so computer modeling can give scientists a window into why the behaviour happens—and can also provide a foundation for designing future technology.

When a photon from the sun strikes a leaf, it sparks a change in a specially designed molecule. The energy knocks loose an electron. The electron, and the "hole" where it once was, can now travel around the leaf, carrying the energy of the sun to another area where it triggers a chemical reaction to make sugars for the plant.

Together, that traveling electron-and-hole-pair is referred to as an "exciton." When the researchers took a birds-eye view and modeled how multiple excitons move around, they noticed something odd. They saw patterns in the paths of the excitons that looked remarkably familiar.

In fact, it looked very much like the behavior in a material that is known as a Bose-Einstein condensate, sometimes known as "the fifth state of matter." In this material, excitons can link up into the same quantum state—kind of like a set of bells all ringing perfectly in tune. This allows energy to move around the material with zero friction. (These sorts of strange behaviors intrigue scientists because they can be the seeds for remarkable technology—for example, a similar state called superconductivity is the basis for MRI machines). According to the models created by the researchers, the excitons in a leaf can sometimes link up in ways similar to exciton condensate behaviour.

Photosynthetic light harvesting is taking place in a system that is at room temperature and what's more, its structure is disordered—very unlike the pristine crystallized materials and cold temperatures that you use to make exciton condensates.

This effect isn't total—it's more akin to "islands" of condensates forming, the scientists say. But that's still enough to enhance energy transfer in the system.

 Anna O. Schouten et al, Exciton-Condensate-Like Amplification of Energy Transport in Light Harvesting, PRX Energy (2023). DOI: 10.1103/PRXEnergy.2.023002

Dead rivers, flaming lakes: India's sewage failure

India at the end of April was projected to have overtaken China as the world's most populous country, according to the United Nations, with almost 1.43 billion people.

Its urban population is predicted to explode in the coming decades, with over 270 million more people forecast to live in its cities by 2040.

But of the 72 billion liters of sewage currently generated in urban centers every day, 45 billion liters—enough to fill 18,000 Olympic-sized swimming pools—aren't treated, according to government figures for 2020-21.

India's sewerage system does not connect to about two-thirds of its urban homes, according to the National Faecal Sludge and Septage Management Alliance (NFSSM).

Many of the sewage treatment plants in operation don't comply with standards— according to media reports.

Coupled with huge volumes of industrial effluent, the sewage is causing disease, polluting India's waterways, killing wildlife and seeping into groundwater.

Part 1

Although India has made major progress in reducing child mortality, diarrhea—caused mostly by contaminated water and food—remains a leading killer.

More than 55,000 children under five died of diarrhea across India in 2019, according to a study published last year in the scientific journal BMC Public Health.

The Yamuna in Delhi is one of the world's filthiest rivers and is considered ecologically dead in places, although people still wash clothes and take ritual baths in it.

It often billows with white foam, and facilities processing drinking water from the river for Delhi's 20 million people regularly shut down because of dangerous ammonia levels.

Despite some bright spots, as well as efforts to plant more trees alongside rivers, the situation elsewhere is often no better in big cities including Mumbai and Chennai.

In Bengaluru, massive Bellandur Lake has on occasion caught fire when methane, generated by bacteria feasting on sewage in the oxygen-depleted water, ignited.

According to the World Bank, India is one of the most "water-stressed" countries in the world, with plummeting water tables and increasingly erratic monsoon rains. India is headed for a water crisis. Sewage can so easily be co-opted to fight that and help us to a very large extent solve the problem in our cities.

India's water is so seasonal. Many cities in India get 50 rain days... but sewage is available every day because you go to the bathroom every day... It's such a powerful weapon.

Children keep falling sick... If they don't get treatment and medicine, the children will die.

Source: 2023 AFP

https://phys.org/news/2023-05-dead-rivers-flaming-lakes-india.html?...

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'Gluing' soft materials without glue!

You're likely familiar with the messy, sticky, frustration-inducing nature of liquid glues. But researchers reporting in ACS Applied Materials & Interfaces now have a brand-new way to weld squishy stuff together without the need for glue at all. They've demonstrated a universal, "electroadhesion" technique that can adhere soft materials to each other just by running electricity through them.

Electroadhesion, in which an electric field is used to hold oppositely charged materials together, forming attachments between the materials' components. This can involve chemical bonds, like ionic bonds, or more physical connections, like ensnaring polymer chains together. Plus, it works with little more than a household battery and pencil lead..

To explore the phenomenon, the team tested a gel in addition to three types of capsules made of alginate or chitosan—both naturally occurring polymers—that were either positively or negatively charged. When attached to graphite electrodes and exposed to a 10-V electric field for around 10 seconds, the oppositely charged materials stuck together.

This bond was strong enough to withstand gravity, and evidence from previous experiments suggests it could last for years. By reversing the flow of electricity, however, the bond was easily broken. .

The researchers also used electroadhesion to sort capsules by their charges, either by laying a charged gel on top of several capsules, or by touching them with a fingertip "robot" that adhered the capsules to themselves. The researchers say that this work demonstrates the universality of electroadhesion and could one day be used in robotics and tissue engineering.

 Leah K. Borden et al, Universal Way to "Glue" Capsules and Gels into 3D Structures by Electroadhesion, ACS Applied Materials & Interfaces (2023). DOI: 10.1021/acsami.2c20793

Birds of a Feather Video-Flock Together: Design and Evaluation of an Agency-Based Parrot-to-Parrot...

Scientists discover the dynamics of an 'extra' chromosome in fruit flies

Most chromosomes have been around for millions of years. Now, researchers  have revealed the dynamics of a new, very young chromosome in fruit flies that is similar to chromosomes that arise in humans and is associated with treatment-resistant cancer and infertility. The findings may one day lead to developing more targeted therapies for treating these conditions.

A new study published in Current Biology on May 4, 2023, reveals how this small chromosome that arose less than 20 years ago has persisted in a single, lab-reared strain of the fruit fly, Drosophila melanogaster, and is correlated with supernumerary (extra) chromosomes in humans.

Supernumerary chromosomes in humans are found in cancer cells and frequently interfere with drugs designed to target tumors, making these types of cancers, like osteosarcoma, difficult to treat. In addition, the presence of supernumerary chromosomes in men can disrupt normal chromosome segregation during sperm production, which can cause infertility.

Being able to understand how supernumerary chromosomes arise and what their structures are can potentially illuminate their vulnerabilities. This may enable the development of potential therapeutic targets.

Called B chromosomes—as opposed to the standard "A" set of essential chromosomes—these genetic elements naturally appeared in a single laboratory stock of fruit flies.

Now, the researchers are witnessing chromosome birth and evolution in less than two decades.

How does something like this new chromosome apparently arise from nothing? More important, as these newly born B chromosomes do not possess any known essential genes for fruit fly function, how do they persist in a genome? In short, by cheating. They do not follow the rules.

Researchers discovered that the fruit fly B chromosomes are maintained by a mechanism called "meiotic drive" that enables the them to rebel against the usual rules of inheritance. The B chromosomes drive their way into the next generation during the formation of the egg to ensure their own persistence in more than half of the next generation.

Part 1

Their genetic background—meaning the unique features in the B chromosome flies' genetic make-up—supports their preferential transmission to the next generation. That buys these  evolutionary time to become a new chromosome, whether that's picking up an essential gene or acquiring something that enables them to better cheat.

Importantly, meiotic drive is a powerful force that can shape how genomes evolve. 

Researchers are also examining how specific mutations can lead to chromosome breakage and new chromosome formation, revealing the mechanism of how supernumeraries arise and become requisite components of a genome.

Stacey L. Hanlon et al, B chromosomes reveal a female meiotic drive suppression system in Drosophila melanogaster, Current Biology (2023). DOI: 10.1016/j.cub.2023.04.028

Part 2

Study finds doctors prescribing untested drug combinations with high addiction potential

The Center for Drug Safety and Effectiveness at Johns Hopkins University has led a study into prescription drug use of multiple concurrent central nervous system (CNS)-active drugs. They found widespread combination prescribing of drugs classified as Schedule II controlled substances with a high potential for psychological or physical dependence and with limited combined clinical trial testing.

The paper, "Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis," published in BMJ Open, examined patterns of medical amphetamine and methylphenidate stimulant drug use, both substances considered to have a high potential for psychological or physical addiction.

Utilizing prescription drug claims for US adults aged 19 to 64 from a commercial insurance claims database with over 9.1 million continuously enrolled adults, stimulant use was defined as adults filling one or more stimulant prescriptions in a single year.

The study identified 276,223 individuals (3.0%) using Schedule II stimulants in 2020. They filled a median of eight prescriptions that provided 227 days of exposure. Among this group, 125,781 (45.5%) combined use of one or more additional CNS active drugs for a median of 213 days. Also, 66,996 (24.3%) stimulant users used two or more additional CNS-active medications for a median of 182  days. Among stimulants users, 131,485 (47.6%) used an antidepressant, 85,166 (30.8%) filled prescriptions for anxiety/sedative/hypnotic medications and 54,035 (19.6%) received opioid prescriptions.

Many adults using Schedule II stimulants simultaneously use one or more additional CNS-active drugs. As these can have tolerance and withdrawal effects or potential recreational abuse, the authors suggest that "discontinuation may be challenging," which is another way of stating that these individuals have likely formed a habitual dependence or addiction possibly requiring intervention or rehabilitation.

Once treatment has started, 75% of patients become long-term users. This underscores the possible risks of non-medical guideline use, noting the issues that warranted the classification of these drugs as having a high potential for psychological or physical dependence and their prominent appearance in toxicology drug rankings of fatal overdose cases.

 Thomas J Moore et al, Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis, BMJ Open (2023). DOI: 10.1136/bmjopen-2022-069668

Deep sleep may mitigate Alzheimer's memory loss, research shows

As the most prevalent form of dementia, Alzheimer's disease destroys memory pathways and, in advanced forms, interferes with a person's ability to perform basic daily tasks. Roughly one in nine people over age 65 have the progressive disease—a proportion that is expected to grow rapidly as the baby boomer generation ages.

In recent years, scientists have probed the ways that deposits of beta-amyloid associate with Alzheimer's disease and how such deposits also affect memory more generally. In addition to sleep being a foundational part of memory retention, the team at UC Berkeley previously discovered that the declining amount of a person's deep sleep could act as a 'crystal ball' to forecast a faster rate of future beta-amyloid buildup in the brain, after which dementia is more likely set in.

A deep slumber might help buffer against memory loss for older adults facing a heightened burden of Alzheimer's disease, new research suggests.

Deep sleep, also known as non-REM slow-wave sleep, can act as a "cognitive reserve factor" that may increase resilience against a protein in the brain called beta-amyloid that is linked to memory loss caused by dementia. Disrupted sleep has previously been associated with faster accumulation of beta-amyloid protein in the brain. However, the new research  reveals that superior amounts of deep, slow-wave sleep can act as a protective factor against memory decline in those with existing high amounts of Alzheimer's disease pathology—a potentially significant advance that experts say could help alleviate some of dementia's most devastating outcomes.

Zsófia Zavecz et al, NREM sleep as a novel protective cognitive reserve factor in the face of Alzheimer's disease pathology, BMC Medicine (2023). DOI: 10.1186/s12916-023-02811-z

Technology enables conversion of mobile phone cameras into high-resolution microscopes

Researchers have developed the world's smallest LED (light-emitting diode) that enables the conversion of existing mobile phone cameras into high-resolution microscopes. Smaller than the wavelength of light, the new LED was used to build the world's smallest holographic microscope, paving the way for existing cameras in everyday devices such as mobile phones to be converted into microscopes via only modifications to the silicon chip and software. This technology also represents a significant step forward in the miniaturization of diagnostics for indoor farmers and sustainable agriculture.

This breakthrough was supplemented by the researchers' development of a revolutionary neural networking algorithm that is able to reconstruct objects measured by the holographic microscope, thus enabling enhanced examination of microscopic objects such as cells and bacteria without the need for bulky conventional microscopes or additional optics. The research also paves the way for a major advancement in photonics—the building of a powerful on-chip emitter that is smaller than a micrometer, which has long been a challenge in the field.

Zheng Li et al, A sub-wavelength Si LED integrated in a CMOS platform, Nature Communications (2023). DOI: 10.1038/s41467-023-36639-1

Iksung Kang et al, Simultaneous spectral recovery and CMOS micro-LED holography with an untrained deep neural network, Optica (2022). DOI: 10.1364/OPTICA.470712

Study finds female astronauts more efficient, suggesting future space missions with all-female crews

As humans contemplate life on other planets, we are immediately confronted with two choices. One is a journey to another solar system that would take tens of thousands of years (with current technology), requiring around 2,000 generations to live out their existence in the cramped confines of a spacecraft while adhering to a strict population control scheme. The other choice is Mars.

Mars has several advantages, not the least of which is proximity, eliminating the need to push people out of airlocks when the spacecraft is at capacity. It would also allow an advance team to set up basic infrastructure and to be the most efficient—the team should all be female.

Researchers from the Space Medicine Team, European Space Agency in Germany have conducted a study published in Scientific Reports that found female astronauts have lower water requirements for hydration, total energy expenditure, oxygen (O₂) consumption, carbon dioxide (CO₂) and metabolic heat production during space exploration missions compared to their male counterparts.

In the study, "Effects of body size and countermeasure exercise on estimates of life support resources during all-female crewed exploration missions," the team utilized an approach developed to estimate the effects of body "size" on life support requirements in male astronauts. For all parameters at all statures, estimates for females were lower than for comparable male astronauts.

When considering the limited space, energy, weight, and life support systems packed into a spacecraft on a long mission, the study finds that the female form is the most efficient body type for space exploration.

Compared to a previous study of theoretical male astronauts, the effect of body size on total energy expenditure was markedly less in females, with relative differences ranging from 5% to 29% lower. Compared at the 50th percentile stature for US females (1.6m), the reductions were even more significant at 11% to 41%. This translates into reduced use of oxygen, production of CO₂, metabolic heat, and water use.

Part 1

When exposed to the prolonged microgravity of space, bad things happen to astronaut bodies. Physiological changes induce muscle atrophy, bone loss, and reduced aerobic and sensorimotor capacity, potentially affecting crewmember health and ability to perform mission tasks.

Exercise in space is called "countermeasure exercise" as it is designed to counter the physiological effects of being weightless. During these exercises (two 30-min aerobic exercises, six days a week), astronauts have higher rates of O₂ consumption, production of CO₂, metabolic heat production, and require more water to rehydrate.

While body size alone correlates to energy metrics (smaller stature, less energy used), missions requiring countermeasure exercise increase this disparity as larger bodies use more energy, need more oxygen, produce more CO₂ and create more heat. Additionally, the study found that females had 29% less water loss through sweating during a single bout of aerobic countermeasure exercise and so required less water to rehydrate.

The theoretical differences between female and male astronauts result from lower resting and exercising O₂ requirements of female astronauts, who are lighter than male astronauts at equivalent statures and have lower relative VO₂max (the rate at which the heart, lungs, and muscles can effectively use oxygen during exercise) values.

The study data, combined with the move towards smaller diameter habitat space for currently proposed mission modules, suggest that there may be several operational advantages to all-female crews during future human space exploration missions, with the most significant improvement coming from shorter females.

Jonathan P. R. Scott et al, Effects of body size and countermeasure exercise on estimates of life support resources during all-female crewed exploration missions, Scientific Reports (2023). DOI: 10.1038/s41598-023-31713-6

Part 2

Fruit fly gut research leads to discovery of new phosphate-storing organelle

Scientists  have discovered something remarkable while studying phosphate transport in fruit fly intestines—a never before seen organelle. Their results are published in the journal Nature, and a News and Views piece in the same journal discusses their findings.

Organelles are the structures performing specific functions within the cell and form the basis for most introductory biology courses. Major organelles include the nucleus, where DNA is kept and translated into RNA; the endoplasmic reticulum, where RNA is translated into proteins; and the Golgi apparatus, where enzymatic processing of proteins takes place; and the mitochondrion, which powers the cell and is involved in monitoring and regulating the cell as well as some intercellular communication.

A few dozen other minor organelles exist within animal cells, and it might have been assumed that every organelle had been discovered after so many years of research. But not so, as detailed in the researchers' new paper, "A phosphate-sensing organelle regulates phosphate and tissue homeostasis."

Immunostaining and ultrastructural analyses showed that PXo specifically appeared in a previously unknown multilamellar membrane—a newly discovered organelle the researchers named PXo bodies. The PXo was essentially storing phosphate in the PXo bodies. When PXo was downregulated or missing, the PXo bodies degraded, releasing the backup storage of phosphate into the cell.

Future investigations will be required to map this new organelle's full functions and interactions and could search for PXo bodies in other life forms.

 Chiwei Xu et al, A phosphate-sensing organelle regulates phosphate and tissue homeostasis, Nature (2023). DOI: 10.1038/s41586-023-06039-y

Emily Strachan et al, Phosphate-storing organelle discovered in fruit flies, Nature (2023). DOI: 10.1038/d41586-023-01410-5

Mobile phone calls linked with increased risk of high blood pressure

Talking on a mobile for 30 minutes or more per week is linked with a 12% increased risk of high blood pressure compared with less than 30 minutes, according to research published recently in European Heart Journal—Digital Health.

It's the number of minutes people spend talking on a mobile that matter for heart health, with more minutes meaning greater risk.

Almost three-quarters of the global population aged 10 and over own a mobile phone. Nearly 1.3 billion adults aged 30 to 79 years worldwide have high blood pressure (hypertension). Hypertension is a major risk factor for heart attack and stroke and a leading cause of premature death globally.

Mobile phones emit low levels of radiofrequency energy, which has been linked with rises in blood pressure after short-term exposure. Results of previous studies on mobile phone use and blood pressure were inconsistent, potentially because they included calls, texts, gaming, and so on.

This study examined the relationship between making and receiving phone calls and new-onset hypertension. The study used data from the UK Biobank. A total of 212,046 adults aged 37 to 73 years without hypertension were included. Information on the use of a mobile phone to make and receive calls was collected through a self-reported touchscreen questionnaire at baseline, including years of use, hours per week, and using a hands-free device/speakerphone.

Participants who used a mobile phone at least once a week to make or receive calls were defined as mobile phone users.

The researchers analyzed the relationship between mobile phone usage and new-onset hypertension after adjusting for age, sex, body mass index, race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood lipids, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels.

Part 1

The average age of participants was 54 years, 62% were women and 88% were mobile phone users. During a median follow up of 12 years, 13,984 (7%) participants developed hypertension. Mobile phone users had a 7% higher risk of hypertension compared with non-users. Those who talked on their mobile for 30 minutes or more per week had a 12% greater likelihood of new-onset high blood pressure than participants who spent less than 30 minutes on phone calls. The results were similar for women and men.

Looking at the findings in more detail, compared to participants who spent less than 5 minutes per week making or receiving mobile phone calls, weekly usage time of 30-59 minutes, 1-3 hours, 4-6 hours and more than 6 hours was associated with an 8%, 13%, 16% and 25% raised risk of high blood pressure, respectively. Among mobile phone users, years of use and employing a hands-free device/speakerphone were not significantly related to the development of hypertension.

The researchers also examined the relationship between usage time (less than 30 minutes vs. 30 minutes or more) and new-onset hypertension according to whether participants had a low, intermediate or high genetic risk of developing hypertension. Genetic risk was determined using data in the UK Biobank.

The analysis showed that the likelihood of developing high BP was greatest in those with high genetic risk who spent at least 30 minutes a week talking on a mobile—they had a 33% higher likelihood of hypertension compared to those with low genetic risk who spent less than 30 minutes a week on the phone.

These  findings suggest that talking on a mobile may not affect the risk of developing high BP as long as weekly call time is kept below half an hour. More research is required to replicate the results, but until then it seems prudent to keep mobile phone calls to a minimum to preserve heart health.

Ye Z, Zhang Y, Zhang Y, et al, Mobile phone calls, genetic susceptibility and new-onset hypertension: results from 212,046 UK Biobank participants, European Heart Journal—Digital Health (2023). DOI: 10.1093/ehjdh/ztad024.

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Part 2

Can fish catch colds?

The simple answer to the question of whether fish can catch a cold is: no. This is because fish don't have lungs or a respiratory tract—or a nose to breathe through, for that matter. This is why you'll never see a fish with a hacking cough or a runny nose.

This isn't to say that fish cannot get ill, of course. "Fish—as well as bivalves such as mussels and oysters and crustaceans such as shrimp—exchange oxygen and CO2through their gills.

Waterborne viruses have evolved to attack the gills in the same way as airborne viruses have evolved to attack the lungs.

Gills are coated with a kind of mucus that acts as a kind of protective barrier. When this mucus is disrupted, this can create openings for viruses to infect the animal. You wouldn't define this infection as a cough or a sneeze, though.

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Researchers discover a potential cause of Parkinson's disease

In 2021, Professor Per Saris's group published results demonstrating that bacteria of the Desulfovibrio bacterial genus correlate with Parkinson's disease, and that their higher number also correlates with the severity of the symptoms of the disease. Replicating the same study, Chinese researchers came to the same conclusion.

The findings indicate that specific strains of Desulfovibrio bacteria are likely to cause Parkinson's disease. The disease is primarily caused by environmental factors, that is, environmental exposure to the Desulfovibrio bacterial strains that cause Parkinson's disease. Only a small share, or roughly 10%, of Parkinson's disease is caused by individual genes.Vy A. Huynh et al, Desulfovibrio bacteria enhance alpha-synuclein aggregation in a Caenorhabditis elegans model of Parkinson's disease, Frontiers in Cellular and Infection Microbiology (2023). DOI: 10.3389/fcimb.2023.1181315

Stroke: Know the signs and risk factors

To recognize the signs of stroke, remember the acronym FAST:

• Face: Does the face droop on one side when the person tries to smile?
• Arms: Is one arm lower when the person tries to raise both arms?
• Speech: Can the person repeat a simple sentence? Is speech slurred or hard to understand?
• Time: During a stroke, every minute counts. If you observe any of these signs, call 911 or your local emergency number immediately.

Risk factors

Many factors can increase the risk of stroke, including:

• Age: People 55 or older have a higher risk of stroke than younger people.
• Race or ethnicity: People who are African American and Hispanic have a higher risk of stroke than people of other races or ethnicities.
• Sex: Men have a higher risk of stroke than women. Women are usually older when they have strokes, and they're more likely to die of strokes than men, however.
• Hormones: Use of birth control pills or hormone therapies that include estrogen increases risk.

Potentially treatable stroke risk factors include lifestyle and medical factors.

Lifestyle risk factors include:

• Being overweight or obese
• Physical inactivity
• Heavy or binge drinking
• Use of illegal drugs, such as cocaine and methamphetamine

Medical risk factors include:

• High blood pressure
• Cigarette smoking or secondhand smoke exposure
• High cholesterol
• Diabetes
• Obstructive sleep apnea
• Cardiovascular disease, including heart failure, heart defects, heart infection or irregular heart rhythm
• Personal or family history of stroke, heart attack or transient ischemic attack
• COVID-19 infection

Mechanical Force on the Skull May Aid Bone Regeneration

By mechanically inducing the expansion of cranial sutures in young adult mice, researchers stimulated stem cell proliferation that is key to healing bone injuries.

Treatments available to repair damage to the skull as a result of trauma, surgery, or congenital anomalies are limited and sometimes involve risks. A study recently published in PNAS (1) offers an alternative approach inspired by how babies regenerate bone tissue. The researchers expanded on previous studies (2,3) showing that open sutures—the fibrous connective tissue holding bones together—in the skulls of newborn mice and humans are reservoirs of skeletal stem cells. The temporary mechanically-induced expansion of closed sutures in young adult mice resulted in the proliferation of skeletal stem cells and facilitated bone regeneration following an injury.

A major contribution of this study is that it advances our knowledge about the impact of external forces on the structure of cranial sutures and the potential healing properties of such impact.

Researchers first compared the cell composition of the calvarial suture—which joins the bilateral bones in the roof of the skull—in mice of different ages and found that the number of skeletal stem cells is significantly reduced in older mice compared to younger mice. Increased numbers of stem cells correlate with open sutures in newborns, leading them to wonder whether expanding the sutures in adults would increase the number of stem cells enough to harness their regenerative potential.

The team achieved this goal in 2-month-old mice, which the researchers considered the equivalent of young adults in humans. When the researchers mechanically induced calvarial suture expansion, the number of skeletal stem cells increased significantly. Moreover, mice that received an injury to the skull near the suture simultaneous to the mechanical expansion exhibited near complete bone regeneration after 60 days, something that was not achieved in control mice without the expansion device. This mechanically-induced regeneration did not occur in 10-month-old mice, probably due to the limited supply of preexisting skeletal stem cells in the sutures, which is insufficient to achieve successful proliferation.

Finally, the team showed that suture stem cell proliferation and the resulting healing effects depend on Wnt signaling, a pathway that regulates key aspects of animal development.

1. Aldawood, Z.A. et al. (2023) “Expansion of the sagittal suture induces proliferation of skeletal stem cells and sustains endogenous calvarial bone regeneration,” Proceedings of the National Academy of Sciences

2. Zhao, H. et al. (2015) “The suture provides a niche for mesenchymal stem cells of Craniofacial Bones,” Nature Cell Biology, 17(4), pp. 386–396. Available at: https://doi.org/10.1038/ncb3139.

3. Maruyama, T. et al. (2016) “Stem cells of the suture mesenchyme in craniofacial bone development, repair and Regeneration,” Nature Communications, 7(1). Available at: https://doi.org/10.1038/ncomms10526.

Cell Senescence

Each cell in an organism has an average life span. For example, cells lining the surface of the human gut or skin typically live 3-5 days before they die.¹ In contrast, stem cells and neurons can survive for many years.² The process by which a cell arrests their growth after completing its life span is called cell senescence.  

Cell senescence is the expression of aging at the cellular level, and the phenomenon occurs when a cell stops dividing and arrests in the G1 phase of the cell cycle.^3,4 During this phase, the cell undergoes numerous phenotypic and metabolic changes. Some of these phenotypic changes include chromatin remodeling with global demethylation and heterochromatin foci formation, which alters the cell’s gene expression landscape.⁵ Additionally, senescent cells are larger in size and more granular.⁶ Senescent cells are eradicated from the body either through apoptosis or by immune cells such as macrophages.⁵

Although cell senescence is often associated with aging, it is an important process during embryogenesis, wound healing, and maintaining homeostasis.⁷ For instance, during central nervous system development, parts of the neural tube undergo senescence for proper formation of the brain and spinal cord.⁸

Cell senescence was first identified by Leonard Hayflick and Paul Moorhead in 1961, when they serially passaged human fibroblast cells in culture.³ They noticed that the cells stopped dividing after 40-60 passages. The number of cell divisions before cell cycle arrest is now known as the Hayflick limit.³

To detect senescent cells in the laboratory, researchers use markers such as senescence-associated B-galactosidase (SABG), which exists in the lysosome of these cells.⁹

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What Triggers Cell Senescence? 
Cell senescence is triggered by a variety of internal or external cellular insults. Examples of internal stresses leading to senescence include shortening of the telomeres, DNA damage, mitochondrial dysfunction, nutrient deprivation, oncogenic pathway activation.⁴ Some examples of external stresses are radiation and chemotherapeutic agents.⁴  

Senescence-Associated Secretory Phenotype 
A major characteristic of senescent cells is the senescence-associated secretory phenotype or SASP.¹⁰ SASP encompasses a senescent cell’s secreted components, or secretome, and includes pro-inflammatory cytokines, chemokines, proteases, growth factors, reactive oxygen species (ROS), and extracellular matrix proteins.¹⁰ Senescent cells use these metabolically active components to communicate with surrounding cells and change the environment in either a positive or negative manner. For instance, SASP can recruit immune cells to remove senescent cells, remodel tissue by secreting angiogenic factors, or promote senescence in other cells through paracrine signalling.¹⁰

Senescence and Aging 

Senescence is an important contributor to aging as it depletes various cell pools, including progenitor and stem cells that can replace damaged tissue over time.¹¹ The SASP of senescent cells enhances inflammation, which increases susceptibility to many age-related diseases, such as heart disease, diabetes, and cancer.¹¹ SASP-mediated paracrine signaling can also encourage neighboring cells to undergo senescence.¹¹

Senescence and Cancer 

A major hallmark of cancer progression is cell proliferation.³ As such, researchers previously thought that the senescence pathway suppressed tumors as it eliminated proliferative cells.¹² However, there is increasing evidence that the SASP may contribute to cancer progression by creating an immunosuppressive environment.¹²

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Anti-senescent Treatments

Researchers have developed drugs called senolytics to selectively target senescent cells that are resistant to apoptosis. These drugs work by upregulating antiapoptotic pathways.⁶ Eliminating these cells is important in diseases such as fibrosis (e.g., pulmonary fibrosis), where tissue is scarred and thickened.¹³ Additionally, patients with obesity or diabetes have high levels of senescent cells in adipose tissue, which contributes to fat cell size.¹⁴ For pulmonary fibrosis and diabetic kidney disease, researchers have conducted clinical trials testing senolytics and observed promising results.⁶

Another class of drugs called senomorphics inhibits SASP.⁶ Reducing SASP is critical for preventing the spread of senescence to neighboring cells or tissues. For example, ruxolitinib reduces inflammation by inhibiting Janus kinases (JAKs), proteins involved in cytokine production.⁹ This drug was shown to be an effective treatment in a chronic obstructive pulmonary disease mouse model.¹⁵

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Footnotes:

 J. Park et al., "Promotion of intestinal epithelial cell turnover by commensal bacteria: role of short-chain fatty acids," PLoS ONE, 11(5):e0156334, 2016. 

2. L. Ottoboni et al., "Therapeutic plasticity of neural stem cells," Front Neurol, 11, 2020.  

3. L. Hayflick, P.S. Moorhead, "The serial cultivation of human diploid cell strains," Exp Cell Res, 25(3):585-621, 1961.

4. Kumari R, Jat P. "Mechanisms of cellular senescence: cell cycle arrest and senescence associated secretory phenotype," Front Cell Dev Biol, 2021.

5. V. Gorgoulis et al., "Cellular senescence: defining a path forward," Cell, 179(4):813-27, 2019.  

6. N.S. Gasek et al., "Strategies for targeting senescent cells in human disease," Nat Aging, 1(10):870-79, 2021. 

7. S. Da Silva-Álvarez et al., "The development of cell senescence," Exp Gerontol, 128:110742, 2019. 

8. M. Storer et al., "Senescence Is a developmental mechanism that contributes to embryonic growth and patterning," Cell, 155(5):1119-30, 2013.  

Part 4

9. W. Huang et al., "Cellular senescence: the good, the bad and the unknown," Nat Rev Nephrol, 18(10):611-27, 2022. 

10. D. McHugh, J. Gil, "Senescence and aging: causes, consequences, and therapeutic avenues," J Cell Biol, 217(1):65-77, 2018.  

11. R. Di Micco et al., "Cellular senescence in ageing: from mechanisms to therapeutic opportunities," Nat Rev Mol Cell Biol, 22(2):75-95, 2021.

12. J. Yang et al., "The paradoxical role of cellular senescence in cancer," Front Cell Devl Biol, 9, 2021. 

13. F. Hernandez-Gonzalez et al., "Cellular senescence in lung fibrosis," Int J Mol Sci, 22(13):7012, 2021. 

14. A.K. Palmer et al., "Senolytics: potential for alleviating diabetes and its complications," Endocrinology, 162(8):bqab058, 2021. 

15. D. Beaulieu et al., "Phospholipase A2 receptor 1 promotes lung cell senescence and emphysema in obstructive lung disease. Euro Respir J, 2021. 

Part 5

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The Human Digestive System Varies a lot from person to person

The human digestive system is much more variable than we tend to think, according to a new study, with significant differences in gut anatomy even among healthy individuals.

This includes individual differences from person to person, the researchers report, plus broader differences such as those between women and men.

In one noteworthy example, the researchers found that women tend to have longer small intestines than men, by an average of 30.7 centimeters.

Because having a longer small intestine helps you extract nutrients from your diet, this finding supports the canalization hypothesis, which posits that women are better able to survive during periods of stress.

The study also revealed more granular differences, suggesting healthy human digestive systems are far more variable than many experts had appreciated.

If you're talking to four different people, odds are good that all of them have different guts, in terms of the relative sizes of the organs that make up that system.

For example, the cecum is an organ that's found at the nexus of the large and small intestine[s]. One person may have a cecum that is only a few centimeters long, while another may have a cecum the size of a coin purse.

The researchers point out that this has big implications for health care, emphasizing the importance of recognizing individual differences in gastrointestinal systems rather than focusing on typical or "normal" anatomy among humans in general.

The researchers point out, however, that humans stand apart for our high variation in intestinal length compared with other species. One possible explanation, they suggest, is that humans don't eat a "standardized captive diet," unlike many other species .

https://peerj.com/articles/15148/

Why should our PC or laptop  restart to install updates?

Software comprises lots of files and programs all interacting. 

When a computer is running software, it loads much of the program into its memory.

If we managed to update that same software on the hard disk or solid state drive (SSD), then the program may panic as everything will be different – it won’t be able to find the files that were there a moment ago. The version in memory will not be compatible with the version on the hard disk or SSD. Lots of errors will be thrown and your computer may crash.

To prevent this, operating systems usually insist that when major updates are needed, we shut down the software being updated, then restart with the new software installed.

Nightmares Can Be Silenced by a Single Piano Chord, Scientists Find

Using non-invasive techniques to manipulate our emotions, it might be possible to curtail the screaming horrors that plague our sleep.

A study last year conducted on 36 patients diagnosed with a nightmare disorder showed that a combination of two simple therapies reduced the frequency of their bad dreams.

Scientists invited the volunteers to rewrite their most frequent nightmares in a positive light and then played sound associated with positive experiences as they slept.

"There is a relationship between the types of emotions experienced in dreams and our emotional well-being. Based on this observation, sceintists had the idea that they could help people by manipulating emotions in their dreams. In this study, they show that they can reduce the number of emotionally very strong and very negative dreams in patients suffering from nightmares.

Many people suffer from nightmares, which aren't always a simple case of a few bad dreams. Nightmares are also associated with poor-quality sleep, which in turn is linked with a whole plethora of other health issues.

Poor sleep can also increase anxiety, which in turn can result in insomnia and nightmares. Recent studies have shown that nightmares and sleep disturbances have seen an uptick during the ongoing global SARS-CoV-2 pandemic.

Given that we don't really understand why, or even how, our brain creates dreams while we sleep, treating chronic nightmares is something of a challenge.

Part 1

One non-invasive method is imagery rehearsal therapy, in which patients rewrite their most harrowing and frequent nightmares to give them a happy ending. Then, they "rehearse" telling themselves that rewritten story, trying to overwrite the nightmare.

This method can reduce the frequency and severity of nightmares, but the treatment is not effective for all patients.

In 2010 scientists found that playing sounds that people have been trained to associate with a certain stimulus, while those people are sleeping, aids in boosting the memory of that stimulus. This has been named targeted memory reactivation (TMR), and researchers wanted to find out if it could improve the effectiveness of imagery rehearsal therapy (IRT).

After having the study's participants complete a dream and sleep diary for two weeks, the volunteers were all given a single IRT session. At this point, half of the group underwent a TMR session, creating a link between a positive version of their nightmares and a sound.

The other half served as a control group, imagining a less horrific version of a nightmare without being exposed to positive sounds.

Both groups received a sleep headphone headband that would play the sound – the piano chord C69 – while they were sleeping, every 10 seconds during REM sleep when nightmares were most likely to occur.

The groups were evaluated after two weeks of additional diary entries, and then again after three months without any sort of treatment.

At the start of the study, the control group had, on average, 2.58 nightmares per week, and the TMR group had an average of 2.94 weekly nightmares. By the end of the study, the control group was down to 1.02 weekly nightmares, while the TMR group had dropped to just 0.19. Even more promising, the TMR group reported an increase in happy dreams.

Part 2

At the three-month follow-up, nightmares had risen slightly in both groups, to 1.48 and 0.33 per week respectively. However, that is still an impressive reduction in the frequency of nightmares, the researchers said, suggesting that using TMR to support IRT results in a more effective treatment.

Researchers observed a fast decrease of nightmares, together with dreams becoming emotionally more positive. For  researchers and clinicians, these findings are very promising both for the study of emotional processing during sleep and for the development of new therapies.

https://www.cell.com/current-biology/fulltext/S0960-9822(22)01477-4

Part 3

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AI could run a million microbial experiments per year, says study

An artificial intelligence system enables robots to conduct autonomous scientific experiments—as many as 10,000 per day—potentially driving a drastic leap forward in the pace of discovery in areas from medicine to agriculture to environmental science. 

 That artificial intelligence platform, dubbed BacterAI, mapped the metabolism of two microbes associated with oral health—with no baseline information to start with. Bacteria consume some combination of the 20 amino acids needed to support life, but each species requires specific nutrients to grow.

Robots trained by artificial intelligence can conduct autonomous experiments, as many as 10,000 per day, to answer scientific questions. New research from University of Michigan engineers shows how automation can help speed the pace of discovery, with ramifications for a variety of fields of study.

Adam C. Dama et al, BacterAI maps microbial metabolism without prior knowledge, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01376-0

Advanced aliens could soon detect life on Earth, say scientists

Aliens on nearby stars could detect Earth through radio signals leaked from the planet, new research suggests.

Researchers used crowd sourced data to simulate radio leakage from mobile towers to determine what alien civilizations might detect from various nearby stars, including Barnard's star, six light years away from Earth.

The research, published in the Monthly Notices of the Royal Astronomical Society journal, found that only more technologically advanced civilizations would be able to detect the current levels of mobile tower radio leakage from Earth. However, as most alien civilizations are likely to have more sensitive receiving systems and as we move towards more powerful broadband systems on Earth, the detectability of humans from other intelligent beings will become more and more likely.

Although it's true we have fewer powerful TV and radio transmitters today, the proliferation of mobile communication systems around the world is profound. While each system represents relatively low radio powers individually, the integrated spectrum of billions of these devices is substantial, according to them.

Current estimates suggest we will have more than one hundred thousand satellites in low Earth orbit and beyond before the end of the decade. The Earth is already anomalously bright in the radio part of the spectrum; if the trend continues, we could become readily detectable by any advanced civilization with the right technology.

Ramiro C Saide et al, Simulation of the Earth's radio-leakage from mobile towers as seen from selected nearby stellar systems, Monthly Notices of the Royal Astronomical Society (2023). DOI: 10.1093/mnras/stad378

Happy worms have healthy eggs

 Worms might not be depressed, per se. But that doesn’t mean they can’t benefit from antidepressants.

In a new study researchers exposed roundworms (a well-established model organism in biological research) to selective serotonin reuptake inhibitors (SSRIs), a class of drugs used for treating depression and anxiety. Surprisingly, this treatment improved the quality of aging females’ egg cells.

Not only did exposure to SSRIs decrease embryonic death by more than twofold, it also decreased chromosomal abnormalities in surviving offspring by more than twofold. Under the microscope, egg cells also looked younger and healthier, appearing round and plump rather than tiny and misshapen, which is common with aging.

Astounded by the results, the researchers replicated the experiment in fruit flies — another common model organism — and the SSRIs demonstrated the same effect.

Although much more work is needed, the researchers say these findings provide new opportunities to explore pharmacological interventions that might combat infertility issues in humans by improving egg quality and by delaying the onset of reproductive aging.

Erin Z. Aprison, Svetlana Dzitoyeva, Ilya Ruvinsky. Serotonergic signaling plays a deeply conserved role in improving oocyte quality. Developmental Biology, 2023; DOI: 10.1016/j.ydbio.2023.04.008

Strange planets

A Chance Event 1 Million Years Ago Changed Human Brains Forever

Like treasured recipes passed down from generation to generation, there are just some regions of DNA that evolution doesn't dare tweak. Mammals far and wide share a variety of such encoded sequences, for example, which have remained untouched for millions of years.

Humans are a strange exception to this club. For some reason, recipes long preserved by our ancient ancestors were suddenly 'spiced up' within a short evolutionary period of time.

Because we're the only species in which these regions have been rewritten so rapidly, they are called 'human accelerated regions' (or HARs). What's more, scientists think at least some HARs could be behind many of the qualities that set humans apart from their close relatives, like chimpanzees and bonobos.

In a new study, researchers found the 3D folding of human DNA in the nucleus is a key factor in this pivotal moment for our species.

A big difference between human and chimpanzee DNA is structural: large chunks of the DNA's building blocks have been inserted, deleted, or rearranged in the human genome. So human DNA folds differently in the nucleus compared with the DNA of other primates.

In a study published earlier this year, researchers created a model suggesting the rapid variations appearing in HARs in early humans often opposed each other, turning the activity of an enhancer up and down in a kind of genetic fine-tuning – a model supported by their new research.

Part 1

For their most recent study, the team compared the genomes of 241 mammal species using machine learning to cope with a large amount of data.

They identified 312 HARs and examined where they are located within the 3D 'neighborhoods' of folded DNA. Almost 30 percent of HARs were in the regions of DNA where structural variations had caused the genome to fold differently in humans compared to other primates.

The team also discovered neighborhoods containing HARs were rich with the genes that differentiate humans from our closest relatives, chimpanzees.

In an experiment that compared DNA within growing human and chimpanzee stem cells, one-third of identified HARs were transcribed specifically during the development of the human neocortex.

Many HARs play a role in embryo development, especially in forming neural pathways associated with intelligence, reading, social skills, memory, attention and focus – traits we know are distinctly different in humans than other animals.

In HARs, these enhancer genes, unchanged for millions of years, may have had to adapt to their different target genes and regulatory domains.

Something big happens like this massive change in genome folding, and our cells have to quickly fix it to avoid an evolutionary disadvantage."

We don't yet understand exactly how these changes have impacted specific aspects of our brain development, and how they became an integral part of our species' DNA. 

https://www.science.org/doi/10.1126/science.abm1696

Part 2

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Replaying outcomes in the brain could predict whether we approach or avoid situations

Past neuroscience studies suggest that when deciding their next actions, mice and other rodents tend to replay past outcomes of similar situations in their brain, which is reflected in a rapid activation of certain brain regions in a sequence. Recently, some studies recorded similar replay-associated brain activity in the human brain using imaging techniques.

Researchers  have carried out a study exploring the possibility that this rapid "replay" of past positive and negative outcomes could predict the choices that humans make in a situation where they could either lose or gain money. Their findings, published in Nature Neuroscience, unveil a possible link between replay in the brain and the planned behaviour of humans, suggesting that while choosing to approach or avoid a situation, humans mentally represent the worst case scenario that could result from their choice.

Researchers wanted to examine how different paths are replayed in the human brain in situations where the outcome is not easy to deduce. Specifically, they examined scenarios in which humans might be conflicted about whether to approach or avoid a given path, a dilemma known as the approach-avoidance conflict.

Choosing whether to stay (avoid) or go (approach) is hard when we're uncertain, and it's possible that replay in the brain could explain how we eventually make up our mind. To test this hypothesis, researchers used a brain imaging technique called magnetoencephalography, which entails the use of a machine that sits on the scalp to pick up the tiny electric currents that pass through human neurons.

Magnetoencephalography allows researchers to precisely measure bursts of activity in different areas of the brain and when they occur. They specifically used it to measure the very fast bursts of brain activity that happen in the brain during replay, which are only about 40 milliseconds apart.

After they collected their brain recordings, the researchers used machine learning to analyze them and determine which of the images they were previously presented with were replayed in the brain while participants made a new decision. In other words, the models they used detected the re-activation of sequences of brain activity that were first recorded while the participants were initially presented with a given image.

By analyzing these results in combination with the decisions that participants took (i.e., whether they approached or avoided a given situation), researchers were then able to determine what sequences were being replayed before participants decided to approach or avoid a given path.

Their biggest finding was that humans play out paths of the worst-case scenario. If participants eventually decided to avoid altogether, they tended to replay (or rather 'simulate') paths leading to the desired but forgone reward. On the other hand, if participants eventually decided to approach and take the risk, they tended to replay paths leading to the feared negative outcome. This sort of counterfactual thinking could be a way for the brain to make sure we don't forget alternative outcomes.

Part 1

The findings gathered by this team of researchers offer some interesting new insight about what past experiences humans tend to replay in their brain before deciding whether to approach or avoid a certain situation.

Jessica McFadyen et al, Differential replay of reward and punishment paths predicts approach and avoidance, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01287-7

Part 2

Early signals of Parkinson's found in gut microbiota of REM sleep behaviour disorder patients

Scientists have found that the gut microbiome holds Parkinson's disease markers and may indicate a method of early diagnosis.

In the study, "Gut microbiome dysbiosis across early Parkinson's disease, REM sleep behavior disorder and their first-degree relatives" published in Nature Communications, the research team looked for correlations in the gut microbiota between comorbid pathologies to see if they could find a causal link.

REM sleep behavior disorder (RBD) causes people to physically act out their dreams while sleeping. RBD affects around 40% of patients with Parkinson's disease (PD), which is also a condition of unintended movements. Patients with RBD are even more likely to acquire PD at some point. The partial overlap in conditions raises interesting questions, and researchers looked to the gut for answers.

In recent years growing knowledge around the gut-brain connection and the relationship between neurological pathologies and microbiota populations has inspired researchers to focus more attention on the role the gut plays in overall human health. While causal relationships are not always clear, correlations between pathologies and microbiota profiles can be strikingly similar across patients with shared diagnoses.

Parkinson's is characterized by the abnormal aggregation of a presynaptic neuronal protein in the central nervous system (spine and brain), alpha-synuclein (α-syn). While this had been considered causal to the pathology, the authors cite studies offering increasing evidence that α-syn pathology has already occurred in the enteric nervous system (neurons embedded into the walls of the gastrointestinal system).

Following the related symptom progression backward, RBD is considered the most specific precursor signal of Parkinson's. Patients with RBD report having an increased prevalence of constipation and increased phosphorylated α-syn immunostaining in their enteric nervous system. Parkinson's patients with RBD features also exhibit these increased constipation and enteric α-syn histopathology effects compared to those without RBD, suggesting a distinct subtype of Parkinson's disease that reflects a gut-brain link of α-synucleinopathy.

The researchers performed a cross-sectional microbiome study across prediagnoses and early stages of the diseases along with controls and RBD relative to disentangle the associations of gut microbiota with the progression of α-synucleinopathy.

The study found gut microbiota compositions significantly altered in early PD and RBD compared with controls and the relative cohort. In RBD patients, the overall microbiota composition shifted closer to those with early Parkinson's.

Random forest modeling identified 12 microbial markers, including depletion of butyrate-producing bacteria and an overabundance of Collinsella, Desulfovibrio, and Oscillospiraceae UCG-005. The profile produced a signal distinct enough to distinguish RBD from controls reliably with machine learning assistance. These findings suggest that Parkinson's-like microbiota profile changes occur at the early stages of RBD-related Parkinson's when RBD first develops.

Another interesting find was the depletion of butyrate-producing bacteria and enrichment of pro-inflammatory Collinsella in RBD relatives, a group that had not yet shared any of the other tell-tale signatures in the microbiota, hinting at a pre-precursor signal that needs further investigation.

Part 1

The study finds markers for pathology pre-symptom progression of Parkinson's disease and REM sleep behavior disorder, highlighting the potential role of gut microbiota in the pathogenesis of α-synucleinopathy. The observations open the door for future research to go beyond the correlations and seek the early causative path of both diseases in hopes of discovering what could be a pre-clinical diagnostic intervention to prevent Parkinson's from developing in the first place.

Bei Huang et al, Gut microbiome dysbiosis across early Parkinson's disease, REM sleep behavior disorder and their first-degree relatives, Nature Communications (2023). DOI: 10.1038/s41467-023-38248-4

Part 2

Study finds that experts support DNA sequencing in newborns

New born babies  undergoing routine newborn screening, a laboratory test to identify the risk of up to 60 treatable conditions is beneficial. Because hundreds of genetic disorders, including a growing number of devastating childhood diseases, now have targeted treatments, including gene and cell therapies, that can offer permanent cures. Despite these advances, the addition of genomic sequencing to newborn screening programs has remained controversial.

Findings from a new study led by researchers  suggest that rare disease experts are now in favour of more expansive newborn testing. In a study published recently in JAMA Network Open, 88% of rare disease experts agreed that DNA sequencing to screen for treatable childhood disorders should be made available to all newborns.

The study further identified 432 gene-disease pairs that are not currently screened for, but that were recommended for newborn screening by more than 50% of the experts. Among the genes that most experts recommended for newborn screening were those associated with a lethal liver and brain disorder, the severe bleeding disorders known as hemophilia A and B, and an increased risk for retinoblastoma, a rare and fatal eye tumour in young children.

Early identification of infants who are at risk for genetic disorders can be lifesaving and screening has the potential to improve health care disparities for affected children.

In many cases in which DNA sequencing identifies a child at risk, a blood test or imaging study can then determine whether the disease condition is already underway, enabling early treatment. In other cases, the child will be entirely healthy despite the positive DNA screen and can be followed for the appearance of symptoms and signs in the future. The researchers note that future studies will be needed to determine whether newborn sequencing is cost-effective and positively contributes to short- and long-term outcomes.

Perspectives of Rare Disease Experts on Newborn Genome Sequencing, JAMA Network Open (2023). DOI: 10.1001/jamanetworkopen.2023.12231

Smallest species shifting the fastest: Bird body size predicts rate of change in a warming world

Birds across the Americas are getting smaller and longer-winged as the world warms, and the smallest-bodied species are changing the fastest.

That's the main finding of a new study of online publication  in the journal Proceedings of the National Academy of Sciences.

The study combines data from two previously published papers that measured body-size and wing-length changes in a total of more than 86,000 bird specimens over four decades in North and South America. One study examined migrating birds killed after colliding with buildings in Chicago; the other looked at nonmigrating birds netted in the Amazon.

Though the two datasets are nonoverlapping in both species composition and geography, and the data were collected independently using different methods, the birds in both studies displayed similarly widespread declines in body size with concurrent increases in wing length.

Now, a new analysis of the combined data has revealed an even more striking pattern: In both studies, smaller bird species declined proportionately faster in body size and increased proportionately faster in wing length.

Both the Chicago and Amazonian studies attributed the reductions in species body size to increasing temperatures over the past 40 years, suggesting that body size may be an important determinant of species responses to climat4e change.

Even so, exactly why smaller-bodied species are changing faster remains an open question, according to the researchers.

 Zimova, Marketa et al, Body size predicts the rate of contemporary morphological change in birds, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2206971120

Recycling plastics might be making things worse

A team of environmental engineers  has found that techniques for recycling plastics may inadvertently lead to increased environmental microplastics. In their study, reported in the Journal of Hazardous Materials Advances, the group tested water used to clean plastic at a recycling plant.

By most accounts, plastic recycling efforts have been a resounding failure. Prior research has shown that only 9% of plastic worldwide is recycled.

This is despite millions of people around the world dutifully separating out their plastic bottles; most of them wind up in landfills anyway. And now, it appears that the recycling process itself might be making things worse. In this new effort, the research team received permission to test a plastic recycling plant to see if it was emitting plastic pollution.

The problem, the researchers note, is that for plastic to be recycled, it must first be cleaned. This is done by washing it in water several times. The rest of the process involves shredding and melting to create pellets. Prior research has suggested washing may result in the release of microplastics into the water. In this new effort, the group found that the plastic was being washed four times. Each water source was tested to find out how much plastic (in the form of micron-sized particles) remained in the water. The research team found microplastics in all four sources. They also noted that most of the water is routed to sewage systems or directly into the environment at most recycling plants. After adding up all the particles they observed, the team estimated that the facility could be emitting approximately 6.5 million pounds of microplastics into the environment each year.

But there was more to the story. The researchers revealed that the facility under study had installed a filtration system, which reduced the number of particles by approximately 50%. However, there was a caveat—the researchers only tested for plastics down to 1.6 microns. Plastic particles can be much smaller than that. Prior research has shown that some can be small enough to make their way into individual cells in an animal's body.

Erina Brown et al, The potential for a plastic recycling facility to release microplastic pollution and possible filtration remediation effectiveness, Journal of Hazardous Materials Advances (2023). DOI: 10.1016/j.hazadv.2023.100309

Nutrition, cognition, and brain health

Rising temperatures are drying up Asia's water tower

Climate models predict that melting glaciers and snowpacks in High Mountain Asia will make one of the largest freshwater reserves unsustainable, threatening water security for Asia’s rapidly growing population.

One of the world’s largest freshwater reserves outside the polar regions, High Mountain Asia is a vast expanse of mountain ranges that encircle the Tibetan Plateau. This area has been recognized as Asia’s water tower for delivering a continuous supply of freshwater into the continent’s major river basins, supplying water to over 2 billion people.

But, as global temperatures continue to rise, evidence shows that water supply in this region is increasingly in danger. In two separate climate models, researchers found that 84% and 97% of the Tibetan Plateau could experience extensive water deficits by the end of the 21st century.

Now, scientists are leveraging this data to help build on immediate policy changes that would protect the future of affected communities in Asia.

A team of researchers from the United States has warned that this critical water resource is on an alarming path of becoming unsustainable due to rising temperatures and climate change, putting downstream communities and biodiversity at serious risk. Their findings were published in Nature.

https://www.nature.com/articles/s41586-022-05643-8

Scientists raise concerns about popular COVID disinfectants

The COVID-19 pandemic has boosted the unnecessary use of antimicrobial chemicals linked to health problems, antimicrobial resistance, and environmental harm, warn more than two dozen scientists in Environmental Science & Technology.

Their critical review details how quaternary ammonium compounds (QACs) are increasingly marketed and used in home, health care, education, and workplace settings despite the availability of safer alternatives and in some cases limited evidence of reduced disease transmission.

Disinfectant wipes containing QACs are often used on children's school desks, hospital exam tables, and in homes where they remain on these surfaces and in the air.  And disinfecting with these chemicals in many cases is unhelpful or even harmful. So experts recommend regular cleaning with soap and water and disinfecting only as needed with safer products.

Human studies have found associations between QACs and asthma, dermatitis, and inflammation. Laboratory animal studies also raise concerns about potential links to infertility, birth defects, and more. Further, there has been evidence dating back to the 1950s that QACs contribute to antimicrobial resistance, making certain bacteria species resistant both to QACs themselves and to critical antibiotics.

It's ironic that the chemicals we're deploying in vain for one health crisis are actually fueling another.

Erica Hartmann et al, Quaternary Ammonium Compounds: A Chemical Class of Emerging Concern, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.2c08244

**

Supercomputers have revealed the giant 'pillars of heat' funneling diamonds upward from deep within Earth

Most diamonds are formed deep inside Earth and brought close to the surface in small yet powerful volcanic eruptions of a kind of rock called "kimberlite."

A supercomputer modeling, published in Nature Geoscience, shows these eruptions are fueled by giant "pillars of heat" rooted 2,900 kilometers below ground, just above our planet's core.

Understanding Earth's internal history can be used to target mineral reserves—not only diamonds, but also crucial minerals such as nickel and rare earth elements.

Part 1

Kimberlite eruptions leave behind a characteristic deep, carrot-shaped "pipe" of kimberlite rock, which often contains diamonds. Hundreds of these eruptions that occurred over the past 200 million years have been discovered around the world. Most of them were found in Canada (178 eruptions), South Africa (158), Angola (71) and Brazil (70).

Between Earth's solid crust and molten core is the mantle, a thick layer of slightly goopy hot rock. For decades, geophysicists have used computers to study how the mantle slowly flows over long periods of time.

In the 1980s, one study showed that kimberlite eruptions might be linked to small thermal plumes in the mantle—feather-like upward jets of hot mantle rising due to their higher buoyancy—beneath slowly moving continents.

It had already been argued, in the 1970s, that these plumes might originate from the boundary between the mantle and the core, at a depth of 2,900km.

Then, in 2010, geologists proposed that kimberlite eruptions could be explained by thermal plumes arising from the edges of two deep, hot blobs anchored under Africa and the Pacific Ocean.

And last year, scientists reported that these anchored blobs are more mobile than they thought.

Geologists assumed that mantle plumes could be responsible for igniting kimberlite eruptions. However, there was still a big question remaining: how was heat being transported from the deep Earth up to the kimberlites?

Researchers used supercomputers  to create three-dimensional geodynamic models of Earth's mantle. Their models account for the movement of continents on the surface and into the mantle over the past one billion years.

They calculated the movements of heat upward from the core and discovered that broad mantle upwellings, or "pillars of heat," connect the very deep Earth to the surface. Their modeling shows these pillars supply heat underneath kimberlites, and they explain most kimberlite eruptions over the past 200 million years.

Part 2

The model successfully captured kimberlite eruptions in Africa, Brazil, Russia and partly in the United States and Canada. 

Towards the center of the pillars, mantle plumes rise much faster and carry dense material across the mantle, which may explain chemical differences between kimberlites in different continents.

Lifesaving solution dramatically reduces severe bleeding after childbirth

A new solution, known as E-MOTIVE, could provide a major breakthrough in reducing deaths from childbirth-related bleeding, according to a landmark study published recently (May 9) in the New England Journal of Medicine by researchers from the World Health Organization (WHO).

Postpartum hemorrhage (PPH)—defined as the loss of more than 500 mL of blood within 24 hours after birth—is the leading cause of maternal mortality worldwide. It affects an estimated 14 million women each year and results in around 70,000 deaths, mostly in low and middle-income countries, equivalent to one death every six minutes.

Postpartum hemorrhage is scary, not always predictable, but absolutely treatable. Nonetheless, its impacts around the world are tragic.

The study, which involved more than 200,000 women in four countries, found that objectively measuring blood loss using a simple, low-cost collection device called a "drape" and bundling together WHO-recommended treatments—rather than offering them sequentially—resulted in dramatic improvements in outcomes for women. Severe bleeding—when a woman loses more than a liter of blood after birth—was reduced by 60%, and they were less likely to die.

There was also a substantial reduction in the rate of blood transfusions for bleeding, which is of particular importance in low-income countries where blood is a scarce and expensive resource.

This new approach to treating postpartum hemorrhage could radically improve women's chances of surviving childbirth globally, helping them get the treatment they need when they need it.

The recommended E-MOTIVE package includes early and accurate detection of PPH using a blood-collection drape. This is complemented by an immediate treatment bundle where indicated, including uterine massage, medicines to contract the womb and stop the bleeding, intravenous fluid administration, an examination and, when needed, escalation to advanced care. In the trial, the E-MOTIVE intervention was supported with an implementation strategy consisting of specific training, PPH trolleys or carry cases, engagement of local champions, audits and feedback. All components of the E-MOTIVE intervention can be performed by midwives.

Ioannis Gallos et al, Randomized Trial of Early Detection and Treatment of Postpartum Hemorrhage, New England Journal of Medicine (2023). DOI: 10.1056/NEJMoa2303966